Alarm systems are known for the purpose of securing a defined area from unauthorized intrusion or trespass. The defined area that is secured by the alarm system will usually comprise a closed area, such as an area in the vicinity of a vehicle.
Alarm systems have certain basic elements in common; they include one or more sensors that are used to sense an entry event or other activity that could be viewed as an unauthorized presence coupled via a communication link to a central unit. When an entry into the defined area is sensed by the sensor, a signal is sent to the control unit, which, if armed, generates an alarm signal. The alarm signal, in turn, may be used locally to sound an audible alarm, such as a loud siren or loud bell (intended to scare off the would-be intruder and to draw attention to the fact that an intrusion or other violation has been detected). The alarm signal may also be used to signal a remote location, such as a police station or a neighboring facility, of the violation that has been detected.